Field
Exemplary embodiments of the present invention relate to an organic light emitting diode (OLED) display.
Discussion of the Background
An organic light emitting diode display includes two electrodes and an organic is emission layer interposed therebetween, wherein electrons injected from a cathode that is one electrode and holes injected from an anode that is the other electrode are bonded to each other in the organic emission layer to form excitons, and light is emitted while the excitons discharge energy.
The organic light emitting diode display includes a plurality of pixels including an organic light emitting diode that is formed of a cathode, an anode, and an organic emission layer, and a plurality of transistors and storage capacitors for driving the organic light emitting diode are formed in each pixel. The plurality of transistors includes a switching transistor and a driving transistor.
When light emitted from the organic light emitting diode is displayed, the light has a range from a black color to a white color according to a driving current Id flowing through the organic light emitting diode, an interval between a gate voltage displaying the black color and a gate voltage displaying the white color is defined as a driving range of the gate voltage. The higher the resolution of the organic light emitting diode display is, the smaller the size of each pixel is, and thus an amount of flowing current per pixel is reduced such that a driving range of a gate voltage applied to a gate electrode of the switching transistor and the driving transistor becomes narrow. Accordingly, it is difficult to adjust the magnitude of the gate voltage Vgs applied to the driving transistor so as to ensure a large grayscale range.
Also, as the organic light emitting diode (OLED) display becomes high resolution, the size of each pixel is decreased such that an interval between the driving voltage line and the data line that are formed with the same layer is decreased, and then a short between the driving voltage line and the data line may be easily generated, and the shorter distances are vulnerable to particles.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.